The invention relates to a bearing and a drive for a spinning rotor unit that has a horizontally arranged shaft to which a rotor is attached, a brake for braking the rotor and cleaning elements that can be applied to the shaft.
Particularly during the processing of synthetic fibers, the so-called supporting disk bearings for open-end spinning rotors, that are used in practice in large numbers, it was found that the smallest fiber components, dust or other deposits will arrive on the shaft and will then be pressed into the running surfaces of the supporting disks. This may result in the shaft no longer rolling uniformly at the supporting disks so that the whole spinning rotor runs erratically.
It has been suggested in German Patent Application No. P 36 30 256.2 (no prior publication) to assign cleaning elements in the form of holding-down jaws to the shaft, in the area of the wedge-shaped gaps. When the brake of the spinning rotor is actuated, these jaws are applied to the shaft. In this construction, a brake is provided that contains a brake block that can be applied to the shaft from the side that faces away from the tangential belt. The holding-down jaws that are used as cleaning elements are arranged on the side of the tangential belt and are applied to the rotor shaft at the same time as the brake lining. So that the shaft remains securely in the wedge-shaped gap during braking, it is provided that the force that is applied by the holding-down jaws is larger than the force applied by the brake. Although an effective cleaning of the rotor shaft can be achieved in the area of the running surfaces of the pairs of supporting disks using this construction, forces affect the shaft of the spinning rotor that are quite high. Also, even if the coefficient of friction of the holding-down jaws is reduced as low as possible, the danger still exists that furrows or the like are cut into the shaft by the holding-down jaws. Furrows of this type, in turn, may result in an untrue run of the shaft and thus an untrue run of the spinning rotor.
An object of the present invention is to provide a bearing and a drive assembly such that the spinning rotor shaft is cleaned when the rotor brake is actuated, such that the forces that are applied for the cleaning are not dependent on the actuating force required to brake the rotor shaft.
This object is achieved by providing braking elements and cleaning elements which are applied to a rotor shaft with a controlled contact force. Actuating elements are provided for activating and deactivating the braking elements and the cleaning elements. The cleaning elements contact force control is independent of the braking elements contact force control.
Although the present invention ensures that the cleaning elements are actuated simultaneously with the brake, the application operation of the cleaning elements and of the brake are completely separate from one another, particularly with respect to the forces that affect the shaft. As a result, it is possible to proportion the cleaning forces such that, on the one hand, an effective cleaning is achieved, while, on the other hand, the shaft is not damaged.
According to other advantageous features of certain preferred embodiments of the invention, it is provided that the cleaning elements are movably held such that gravitational force is used as the application force. As a result, it is possible to proportion the cleaning forces via the dead weight of the cleaning elements and their holding elements.
According to other advantageous features of certain preferred embodiments of the invention, it is provided that the cleaning elements are mounted at swivel arms that can be swivelled around a stationary axis that is essentially parallel to the shaft of the spinning rotor. Because the cleaning elements act into the wedge-shaped gaps in these embodiments, no problems occur with respect to a time sequence.
According to other advantageous features of certain preferred embodiments of the invention, it is provided that the actuating elements of the brake contain support devices for holding elements of the cleaning elements that, when the brake is actuated, can be moved out of the path of motion of the holding elements of the cleaning elements that is directed toward the shaft. As a result, it is achieved in a simple way that, when the brake is actuated, the application of the cleaning elements is released on the basis of a dead weight or, if necessary, it is contemplated to use additional forces that are controlled by means of spring elements, while, on the other hand, when the brake is released, the cleaning elements are lifted off the shaft.
According to other advantageous features of certain preferred embodiments of the invention, it is provided that the actuating elements of the brake are coupled with elements for lifting off a pressure roller which is applied to the tangential belt during the driving of the shaft. The lifting off elements are in turn coupled with holding elements of the cleaning elements. As a result, a favorable utilization of space is made possible because the pressure roller and the holding elements for the cleaning elements are arranged on the same side with respect to the tangential belt. Thus, it is contemplated to implement constructionally advantageous solutions. Further, it is also advantageous that the cleaning elements can be actuated with the holding elements in opposite direction of the pressure roller.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.